Erdős Problem a Daythe open tracker

Erdős Problem #159

OPENdatabase updated 2025-08-31

No proof or disproof is known, and it isn't known whether a finite computation could settle it.

What the community database records, not our verdict. erdosproblems.com no longer shows statuses (why).

There exists some constant \(c>0\) such that \[R(C_4,K_n) \ll n^{2-c}.\] The prize of $100 is offered in [Er78] for a proof or disproof. This problem is #17 in Ramsey Theory in the graphs problem collection.
Statement as formalized in Formal Conjectures (Google DeepMind, Apache-2.0) · their label: research open. The authoritative wording is on erdosproblems.com/159.
Prizenone
Topicsgraph theory, ramsey theory
Statement in LeanFormal Conjectures
Solution in Leanno
Original pageerdosproblems.com/159
EARLY RUN BY THIS SITE · JUL 25, 2026

No polynomial improvement in either direction. Open ($100).

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